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<title>Environment Variables (GNU libgomp)</title>

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<h2 class="chapter" id="OpenMP-Environment-Variables"><span>4 OpenMP Environment Variables<a class="copiable-link" href="#OpenMP-Environment-Variables"> &para;</a></span></h2>

<p>The environment variables which beginning with <code class="env">OMP_</code> are defined by
section 4 of the OpenMP specification in version 4.5, while those
beginning with <code class="env">GOMP_</code> are GNU extensions.
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<li><a href="OMP_005fCANCELLATION.html" accesskey="1"><code class="env">OMP_CANCELLATION</code> &ndash; Set whether cancellation is activated</a></li>
<li><a href="OMP_005fDISPLAY_005fENV.html" accesskey="2"><code class="env">OMP_DISPLAY_ENV</code> &ndash; Show OpenMP version and environment variables</a></li>
<li><a href="OMP_005fDEFAULT_005fDEVICE.html" accesskey="3"><code class="env">OMP_DEFAULT_DEVICE</code> &ndash; Set the device used in target regions</a></li>
<li><a href="OMP_005fDYNAMIC.html" accesskey="4"><code class="env">OMP_DYNAMIC</code> &ndash; Dynamic adjustment of threads</a></li>
<li><a href="OMP_005fMAX_005fACTIVE_005fLEVELS.html" accesskey="5"><code class="env">OMP_MAX_ACTIVE_LEVELS</code> &ndash; Set the maximum number of nested parallel regions</a></li>
<li><a href="OMP_005fMAX_005fTASK_005fPRIORITY.html" accesskey="6"><code class="env">OMP_MAX_TASK_PRIORITY</code> &ndash; Set the maximum priority</a></li>
<li><a href="OMP_005fNESTED.html" accesskey="7"><code class="env">OMP_NESTED</code> &ndash; Nested parallel regions</a></li>
<li><a href="OMP_005fNUM_005fTEAMS.html" accesskey="8"><code class="env">OMP_NUM_TEAMS</code> &ndash; Specifies the number of teams to use by teams region</a></li>
<li><a href="OMP_005fNUM_005fTHREADS.html" accesskey="9"><code class="env">OMP_NUM_THREADS</code> &ndash; Specifies the number of threads to use</a></li>
<li><a href="OMP_005fPROC_005fBIND.html"><code class="env">OMP_PROC_BIND</code> &ndash; Whether threads may be moved between CPUs</a></li>
<li><a href="OMP_005fPLACES.html"><code class="env">OMP_PLACES</code> &ndash; Specifies on which CPUs the threads should be placed</a></li>
<li><a href="OMP_005fSTACKSIZE.html"><code class="env">OMP_STACKSIZE</code> &ndash; Set default thread stack size</a></li>
<li><a href="OMP_005fSCHEDULE.html"><code class="env">OMP_SCHEDULE</code> &ndash; How threads are scheduled</a></li>
<li><a href="OMP_005fTARGET_005fOFFLOAD.html"><code class="env">OMP_TARGET_OFFLOAD</code> &ndash; Controls offloading behaviour</a></li>
<li><a href="OMP_005fTEAMS_005fTHREAD_005fLIMIT.html"><code class="env">OMP_TEAMS_THREAD_LIMIT</code> &ndash; Set the maximum number of threads imposed by teams</a></li>
<li><a href="OMP_005fTHREAD_005fLIMIT.html"><code class="env">OMP_THREAD_LIMIT</code> &ndash; Set the maximum number of threads</a></li>
<li><a href="OMP_005fWAIT_005fPOLICY.html"><code class="env">OMP_WAIT_POLICY</code> &ndash; How waiting threads are handled</a></li>
<li><a href="GOMP_005fCPU_005fAFFINITY.html"><code class="env">GOMP_CPU_AFFINITY</code> &ndash; Bind threads to specific CPUs</a></li>
<li><a href="GOMP_005fDEBUG.html"><code class="env">GOMP_DEBUG</code> &ndash; Enable debugging output</a></li>
<li><a href="GOMP_005fSTACKSIZE.html"><code class="env">GOMP_STACKSIZE</code> &ndash; Set default thread stack size</a></li>
<li><a href="GOMP_005fSPINCOUNT.html"><code class="env">GOMP_SPINCOUNT</code> &ndash; Set the busy-wait spin count</a></li>
<li><a href="GOMP_005fRTEMS_005fTHREAD_005fPOOLS.html"><code class="env">GOMP_RTEMS_THREAD_POOLS</code> &ndash; Set the RTEMS specific thread pools</a></li>
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